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Brain Death
Brain Death
Death : Definition
Content
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Death is the complete and irreversible stoppage of
Circulation
Respiration
 Brain function (Tripod of life)
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What is brain death?
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Causes of brain death
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Clinical evaluation of brain death
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Brain death diagnosis
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Procedure after brain death diagnosis
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Mechanical Ventilator use in ICU
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18 April 2018
Umesh Jayarajah
Brain Death

Ireversible destruction of the brain,with the
Conditions Distinct from Brain Death


Coma: a state of unarousable (impairment of arousal) unresponsiveness
(impairment of cognitive content) in which the subject lies with their eyes
closed. There is no spontaneous eye opening, response to voice, localization
to painful stimuli or verbal output.

Persistent Vegetative State: vegetative state present one month after acute
traumatic or nontraumatic brain injury or lasting for at least one month in
patients with degenerative or metabolic disorders or developmental
malformations. a state of partial arousal rather than true awareness
resulting total absence of all cortical and
brainstem functions,although spinal cord
Brought concept of “Brain Death”
refleves may remain

Locked in Syndrome: A neurological disorder characterized by complete
paralysis of voluntary muscles in all parts of the body except for those that
control eye movement. The locked-in syndrome is usually a complication of
a cerebrovascular accident (a stroke) in the base of the pons in the
brainstem.
3 clinical findings necessary to confirm
irreversible cessation of all functions of the
entire brain, including brain stem
 Coma
(with a known cause)
brainstem reflexes
 Apnoea
 Absence of
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Brain Death : Mechanism

Neuronal Injury
Decreased Intracranial
Blood Flow
Increased Intracranial
Pressure
2. Absence of cortical functions

The Clinical Evaluation: 2 independent physicians
Neuronal Swelling
ICP > MAP is
incompatible
with life
No spontaneous movement, eye opening, or movement
or response after auditory, verbal, or visual commands
Clinical evaluation of brain death
4 Steps in Determining Brain Death



The Neurologic Assessment
Ancillary Test
Documentation
1. Irreversible coma
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Known etiology and or reversible causes ruled out
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Must have an absence of possible irreversible causes
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Hypothermia (>32.50C)
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Neuromuscular blockade and Shock
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Significant levels of sedatives
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Severe metabolic distrubance and Endocrine abnormalities
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Poisoning
Pupillary reflex-
3. Absence of brain stem function
1)Pupillary reflex
2)Corneal reflex

Midposition or dilated (4 to 9 mm)
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Absent pupillary light reflex
3)Gag reflex

Cerebral motor response to pain
 Supraorbital ridge, trapezius
 Motor responses may occur spontaneously during
apnea testing (spinal reflexes)
4)Cough reflex
5)Oculocephalic reflex (doll’s eye reflex)
6)Oculovestibular reflex (caloric reflex)
*Topical administration of drugs and eye trauma may
influence pupillary size and reactivity
7)No integrated motor response to pain
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Spinal arcs are intact!!!
8)Apnea testing
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Corneal reflex
Corneal reflexes are absent in brain death
 Corneal reflexes - tested by using a cotton-tipped
swab
Oculocephalic reflex
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Rapidly turn the head 90° on both sides
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Normal response = deviation of the eyes to the
opposite side of head turning (Doll’s eye)
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Brain death = oculocephalic reflexes are absent (no
Doll’s eyes) = no eye movement in response to head
movement
Brain Death : Apnoea Test
Vestibularocular reflex

No eye movements within 3 mints after irrigating each tympanic
membrane (if intact) sequentially with 50 ml ice water for 30 to 45 seconds
while the head of the supine patient is elevated 30 degrees

Reduce Ventilation frequency to 10/min
Reduce PEEP to 5 Cm H2O
Take 1st Blood sample for Blood Gas analysis
Disconnect Ventilator
Deliver 100% O2 by catheter through ET tube
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Observe for Respiratory Movement
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Interpreting the test
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The apnea test is POSITIVE (i.e., supports the
diagnosis of brain death) if:
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There are no respiratory efforts during the test AND
Repeat ABG shows PCO2 > 60 mm Hg.
@ 6 L/min
Atleast for 8 – 10 min
Retained vestibulocular reflex
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4. Brain Death
Ancillary Confirmatory Testing

Recommended when
Proximate cause of coma is not known or
 When confounding clinical conditions limit clinical
examination
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EEG
Cerebral Angiography
PET : Glucose Metabolic Studies
Somato-Sensory Evoked Potential
Once brain death has been diagnosed
References
•
Notify next of kin
1.
•
Interval observation period : 6 hours
Goila AK, Pawar M. The diagnosis of brain death. Indian
Journal of Critical Care Medicine : Peer-reviewed, Official
Publication of Indian Society of Critical Care Medicine.
2009;13(1):7-11. doi:10.4103/0972-5229.53108.
•
Repeat clinical assessment
2.
•
Confirmatory testing as indicated
John Oram, Paul Murphy; Diagnosis of death, Continuing
Education in Anaesthesia Critical Care & Pain, Volume 11,
Issue 3, 1 June 2011, Pages 77–81
•
Certification of brain death and documentation
•
Withdraw cardio-respiratory support in accordance with
hospital policies, including those for organ donation
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